Amioidinae new subfamily Fraser & Mabuchi

Type genus Amioides Smith & Radcliffe in Radcliffe 1912

Diagnosis. Incomplete, based on radiographs and external characters: Two dorsal fins VIII or IX dorsal spines deeply divided as VII or VIII+I,9–10; anal fin II,7–8; internal support of spines by serial proximal-middle radials closely associated, 6th and 7th elements broadening at fin division; two supernumerary dorsal spines; three supraneurals; first anal proximal-middle radial straight; 15 branched caudal fin-rays, upper and lower unbranched; preopercle ridge smooth, preopercle edges serrate; large supramaxilla; basisphenoid present; vertebrae10+14; rodlike ribs on 3rd to 10th vertebrae; epineurals present on ribs of 3rd to 8th vertebrae; PU2 and PU3 with autogenous haemal spines; two pairs of uroneurals; hypurals 1–5 present, not fused; parhypural free; three epurals; perforated anterior ceratohyal; posttemporal serrate or one or two large spines on edge; cephalic pore system complex with many small pores and canal flutes; multiple pores in lateral-line scales, many free neuromast on lateral-line scales; lateral-line scales large, 24–25, ctenoid; mouth brooding of eggs unknown.

Distribution. Amioides is a deep-dwelling (77–267 m) genus known from limited material. The collection sites support the conclusion that it is widespread from continental locations and islands of the Indo-Pacific of East Africa to Japan and Vanuatu (Fraser 2013a). Holapogon is a deeper-dwelling (38–100 m) genus known from limited material from the Andaman Islands and in the Arabian Sea along the west coast of India and Oman. It should be expected along the coast of Yemen and possibly Somalia.

Remarks. This subfamily contains two genera, two species: Amioides polyacanthus and Holapogon maximus (Boulenger 1888). Although the latter species was absent from the present molecular analyses, it is placed in this subfamily based on the morphology (see Fraser 1973). Among cardinalfishes the presence of a deeply divided spinous dorsal fin with IX dorsal spines, a visible, but small, eighth dorsal spine, a large supramaxilla shaped lacking an slender antero-proximal point, multiple pores in lateral-line scales with multiple free neuromasts on the lateral-line scales, serrated preopercular edge, perforated anterior ceratohyal, caudal skeleton (three epurals, two pairs of uroneurals, five free hypurals a free parhypural), ribs on 3rd to 10th vertebrae, nine epineurals and vertebrae arrangement with median fins are all plesiomorphic family characters. These characters plus other family characters possessed by this subfamily should be very useful in the hunt for close family relatives. The cephalic arrangement of pores and flutes are likely synapomorphies that united these two large, relatively deep-dwelling genera (Bergman 2004). Other possible synapomorphies await more detailed studies. The osteology of both species has not been studied with cleared and counter stained small specimens. No small specimens, <80 mm SL exist in collections, only large adults up to 198 mm SL (Fraser 2013a).